Association between glomerular filtration rate and plasma N-terminal pro-atrial natriuretic peptide concentration in dogs

OBJECTIVES

To investigate the association between plasma N-terminal pro-atrial natriuretic peptide concentration and glomerular filtration rate in dogs.

MATERIALS AND METHODS

Dogs were classified into four categories by bodyweight. Dogs were divided into four groups (Groups 1 to 4) based on glomerular filtration rate estimates using plasma iohexol clearance per bodyweight category. Generalised linear models were built to explore the relationship between plasma N-terminal pro-atrial natriuretic peptide concentration and glomerular filtration rate and the effect of confounders on plasma N-terminal pro-atrial natriuretic peptide concentration.

RESULTS

Fifty-three dogs were included (Group 1, 25; Group 2, seven; Group 3, five; and Group 4, 16). The medians (interquartile range) N-terminal pro-atrial natriuretic peptide concentrations for Groups 1 to 4 were 7224 pg/mL (4766 to 10,254 mg/dL), 8958 pg/mL (4935 to 11,271 mg/dL), 9280 pg/mL (9195 to 10,384 mg/dL) and 12,683 pg/mL (9133 to 19,217 mg/dL), respectively. Group 4, estimated to have the highest reduction in glomerular filtration rate, had a higher plasma N-terminal pro-atrial natriuretic peptide concentration than Groups 1 to 3. Based on the final generalised linear model, influencing factors for plasma N-terminal pro-atrial natriuretic peptide concentration were plasma iohexol clearance (-0.136; 95% confidence interval, -0.227 to -0.046) and bodyweight (-0.058; 95% confidence interval, -0.098 to -0.018).

CLINICAL SIGNIFICANCE

N-terminal pro-atrial natriuretic peptide concentration is associated with the glomerular filtration rate.

[Thymoma with long-term survival treated by polysurgery; report of a case]

A 50-year-old man was found to have a chest abnormal shadow during a check-up and visited our hospital in 1991. Tumor shadow was observed in the anterior mediastinum. Resection of the tumor was performed by partial thymectomy. The pathological diagnosis was a thymoma type B1 and stage I based on Masaoka' s classification. In 2004, he underwent radical thymectomy and partial resection of the lung to remove the local recurrent tumor followed by postoperative radiation therapy. In 2006, 3rd operation was performed and the tumor in the superior mediastinum was resected. Since then, the patient is well without signs of recurrence. We experienced a case of thymoma with long-term survival treated by polysurgery.

Complement Receptor Type 3 (CR3)- and Fc Receptor (FcR)-Mediated Matrix Metalloproteinase 9 (MMP-9) Secretion and Their Intracellular Signalling of Bovine Neutrophils

Complement receptor type 3 (CR3)- and Fc receptor (FcR)-mediated metalloproteinase-9 (MMP-9) secretion and their intracellular signalling of bovine neutrophils were evaluated. Relative density of MMP-9 secreted by neutrophils stimulated with opsonized zymosan (OPZ, stimulant for CR3) was significantly (p < 0.05) increased when the OPZ concentration was increased from 0 to 0.4 mg/ml. Similar results were obtained for neutrophils stimulated with heat-aggregated IgG (Agg-IgG, stimulant for Fc receptor) at concentrations from 0 to 0.40 mg/ml. Preincubation of neutrophils with 1-30 nmol/L wortmannin (phosphoinositide 3-kinase inhibitor) resulted in inhibition of MMP-9 secretion induced by stimulation with OPZ and Agg-IgG in a concentration-dependent manner, 30 nmol/L wortmannin causing complete inhibition. Similarly, preincubation of neutrophils with 0-100 mumol/L genistein (tyrosine kinase inhibitor) also resulted in inhibition of OPZ- and Agg-IgG-induced MMP-9 secretion in a concentration-dependent manner, with 100 micromol/L genistein causing complete inhibition. Significant (p < 0.05) positive correlations were found between MMP-9 and luminal-dependent chemiluminescent response (LDCL) in the case of stimulation with OPZ (r = 0.754) and in the case of stimulation with Agg-IgG (r = 0.728). Our findings suggested that CR3 and FcR play a critical role in production of MMP-9 and may be regulated by intracellular signal transduction, including that by phosphoinositide 3-kinase (PI3K) and tyrosine kinase (TK).

Di-(2-ethylhexyl) phthalate suppresses tamoxifen-induced apoptosis in GH3 pituitary cells

Tamoxifen, an estrogen receptor antagonist, has been clinically used as an antitumor drug and induces apoptosis in GH3 pituitary cells. Although di-(2-ethylhexyl) phthalate (DEHP) is a well-known environmental estrogen and the exposure to this chemical is well expected, reports are limited regarding effects of DEHP on tamoxifen-induced apoptosis in pituitary cells. In the cytotoxicity assay, the reduced cell viability in tamoxifen-treated GH3 cells was reversed by DEHP (250 microM) treatment for 4 days. To characterize cell death, cells were stained using Hoechst 33258. Apoptotic morphological change such as chromatin condensation induced by tamoxifen was suppressed by treatment with DEHP. Flow cytometric analysis revealed that the number of apoptotic cells induced by tamoxifen was significantly decreased by DEHP treatment. Enhanced poly (ADP-ribose) polymerase (PARP) cleavage by tamoxifen treatment was also inhibited by DEHP. These results suggest that DEHP suppresses tamoxifen-induced apoptosis in association with its estrogenic effect in GH3 cells and might counteract the therapeutic effect of tamoxifen.

Analysis of acrylamide by LC-MS/MS and GC-MS in processed Japanese foods

Acrylamide concentrations in processed foods (63 samples covering 31 product types) from Japan were analysed by LC-MS/MS and GC-MS methods. The limit of detection and limit of quantification of acrylamide were 0.2 ng x ml(-1) (6 fmol) and 0.8 ng x ml(-1) (22 fmol), respectively, by LC-MS/MS, and those of 2,3-dibromopropionamide derived from acrylamide were 12 ng x ml(-1) (52 fmol) and 40 ng x ml(-1) (170 fmol), respectively, by GC-MS. Repeatability given as RSD was <5 and <15% for the LC-MS/MS and GC-MS methods, respectively. High correlation (r(2) - 0.946) was observed between values obtained by the two methods. Most potato crisps and whole potato-based fried snacks showed acrylamide concentrations >1000 microg x kg(-1). The concentrations in non-whole potato-based snacks, rice crackers processed by grilling or frying, and candied sweet potatoes were lower compared with those in the potato crisps and the whole potato-based fried snacks. One of the whole potato-based fried snacks, however, showed low acrylamide concentration (<50 microg x kg(-1)) suggesting the formation of acrylamide is strongly influenced by processing conditions. Acrylamide concentrations in instant precooked noodles and won-tons were <100 microg x kg(-1) with only one exception. Roasted barley grains for 'Mugi-cha' tea contained 200-600 microg x kg(-1) acrylamide.

Treatment of A-pattern esotropia with marked mongoloid slanting palpebral fissures

BACKGROUND

The association of oblique palpebral fissures and A- or V-pattern has not been clarified. We report two cases of A-pattern esotropia with marked mongoloid slanting palpebral fissures associated with vertical displacement of the horizontal rectus muscle.

CASES

Case 1 was a boy with Prader-Willi syndrome. He showed A-pattern esotropia with upward slanting palpebral fissures. Severe superior oblique muscle overaction was observed. Case 2 was a girl with meningocele. She also showed A-pattern esotropia with upward slanting palpebral fissures.

OBSERVATIONS

In case 1, weakening surgery of the superior oblique muscles did not improve the A-pattern. Coronal images of computed tomography showed one-half-muscle-width upward displacement of both lateral rectus muscles. After downward transposition surgery of the lateral rectus muscles, the preoperative A-pattern of 25 prism diopters (PD) was successfully corrected to 10 PD. In case 2 also, upward displacement of both lateral rectus muscles was shown by computed tomography. The preoperative A-pattern of 26 PD was corrected to 4 PD postoperatively after upward transposition surgery of the medial rectus muscles.

CONCLUSIONS

The vertical displacement of horizontal rectus muscles was considered the principal cause of A-pattern in these cases associated with marked mongoloid slanting palpebral fissures.

Responses of a model legume Lotus japonicus to lipochitin oligosaccharide nodulation factors purified from Mesorhizobium loti JRL501

Lotus japonicus has been proposed as a model legume for molecular genetic studies of symbiotic plant-microbe interactions leading to the fixation of atmospheric nitrogen. Lipochitin oligosaccharides (LCOs), or Nod factors, were isolated from the culture of Mesorhizobium loti strain JRL501 (MAFF303099), an efficient microsymbiont of L. japonicus B-129 cv. Gifu. High-performance liquid chromatography and mass spectrometric analyses allowed us to identify at least five different structures of LCOs that were produced by JRL501. The major component was NodMl-V(C18:1, Me, Cb, AcFuc), an N-acetyl-glucosamine pentamer in which the nonreducing residue is N-acylated with a C18:1 acyl moiety, N-methylated, and carries a carbamoyl group and the reducing N-acetylglucosamine residue is substituted with 4-O-acetyl-fucose. Additional novel LCO structures bearing fucose instead of acetyl-fucose at the reducing end were identified. Mixtures of these LCOs could elicit abundant root hair deformation on L. japonicus roots at a concentration of 10(-7) to 10(-9) M. Spot inoculation of a few nanograms of LCOs on L. japonicus roots induced the formation of nodule primordia in which the early nodulin genes, ENOD40 and ENOD2, were expressed in a tissue-specific manner. We also observed the formation of a cytoplasmic bridge (preinfection thread) in the swollen outermost cortical cells. This is the first description of cytoplasmic bridge formation by purified LCOs alone in a legume-forming determinate nodules.

Protein anatomy: structure and function of peptide fragments corresponding to the secondary structure units of barnase

Globular proteins can be decomposed into several modules or secondary structure units. It is useful to investigate the functions of such structural units in order to understand the folding units of proteins. In our previous work, barnase was divided into six peptide fragments corresponding to modules, and some of them were shown to have RNA-binding and RNase activity [Yanagawa, et al. (1993) J. Biol. Chem. 268, 5861-5865]. Barnase mutant proteins obtained by permutation of the structural units also had RNase activity [Tsuji, T. et al. (1999) J. Mol. Biol. 286, 1581-1596]. Here we investigated the structure and function of peptide fragments corresponding to secondary structure units of barnase. The results of circular dichroism spectroscopy indicated that some of the peptide fragments form helical structures in aqueous solutions containing over 30% 2,2,2-trifluoroethanol, and the S6 (94-110) peptide fragment is induced to form a beta-sheet structure in the presence of RNA. The S6 peptide fragment forms aggregate complexes with RNA. Electron microscopic analysis showed that the aggregate complexes were comprised of filaments. These results indicate that not only modules but also secondary structure units dissected from a globular protein have functional and structure-forming capabilities.

Inflammatory stimuli increase prostaglandin D synthase levels in cerebrospinal fluid of rats

To examine the possibility that prostaglandin D synthase in CSF is involved in the brain responses to inflammation, we monitored the enzyme levels before and after administration of a bacterial endotoxin lipopolysaccharide (LPS) or proinflammatory cytokines. After an i.p. injection of LPS, the synthase levels began to rise within 1 day, peaked at 2 days and returned to the basal by 5 days after injection. The enzyme levels increased in a similar manner in response to tumor necrosis factor-alpha or interleukin (IL)-1 beta injected i.v. Centrally administered IL-1 beta had a similar effect. These findings support the hypothesis that PGD synthase in CSF participates in the brain responses to inflammation.

Infrared intensity of 1-monolaurin-water systems in the gel phase

The infrared spectra of 1-monolaurin-water systems, where KSCN is added as the intensity standard, were observed and the infrared intensity of the bands due to acyl groups measured relatively to that of the CN stretching. The infrared intensities of the bands parallel and perpendicular to the paraffin chains decrease and increase, respectively, on going from the crystalline 1 phase to the gel phase, confirming that these intensity changes result from the long-range interaction among oscillating dipoles. The infrared spectra with no CH2 rocking and the splitting of the CH2 rocking are also discussed with the same interaction model.

Vascularized iliac bone graft for avascular necrosis of the femoral head

This is a followup study of 31 hips in 24 patients from 2 to 11 years after receiving a vascularized iliac bone graft for nontraumatic avascular necrosis of the femoral head. The clinical results according to the Merle d'Aubigne score were satisfactory in 24 (77%) of the hips, whereas the radiographic success rate for all hips was 58%. The extent of the lesion as shown on anteroposterior radiographs was predictive of the eventual outcome. Seven (39%) of 18 hips with a lateral type lesion had satisfactory results, whereas 11 (85%) of 13 hips with a medial type lesion had satisfactory results. All of the hips with a medial type lesion and a lateral head index of greater than 12% had satisfactory results. For the success of this procedure, the lateral buttress of the normal portion in the femoral head was necessary.

Bone particles disturb new bone formation on the interface of the titanium implant after reaming of the marrow cavity

Histomorphometric studies were conducted in rats to determine whether bone particles would disturb new bone formation on the interface of titanium implants inserted after reaming of the marrow cavity. In eighty 10-week-old female Wistar rats, smooth-surfaced titanium alloy implants were inserted bilaterally into the marrow cavity after reaming in the distal femur. There were three experimental groups: in the irrigated femora, sterile saline was flushed through the medullary canal; in the particle femora, autologous bone particles were inserted into the intramedullary cavity; and in the reamed femora, the implant was inserted without procedures after reaming. The rats were sacrificed at one, two, four or eight weeks postoperatively, and Villanueva bone staining was applied for histomorphometric studies. The bone volume of new bone on the interface of the implant in the irrigated femora was greater than that in the particle or the reamed femora throughout the study period. The results suggest that clearance of bone particles by irrigation after reaming of the marrow cavity significantly facilitates new bone formation on the interface of implants by one week. The findings also suggest the potential clinical application of total canal irrigation prior to insertion of cementless femoral components as well as cemented prosthesis.

Isolation of active ribozymes from an RNA pool of random sequences using an anchored substrate RNA

To analyze the structure-function relationship of a ribozyme, RNA molecules with cleavage activities were isolated from a pool of RNAs that have a region of 14 random nucleotides for catalysis by a novel in vitro selection method. Active ribozymes from the pool were selected using a substrate RNA anchored to an agarose bead. After 7 or 8 selection cycles, the pool of the selected molecules showed cleavage activity against the substrate RNA. Structures and catalytic activities of the individual selected RNA molecules were then analyzed by cDNA cloning, in vitro transcription and cleavage reactions. All the active ribozymes were found to catalyze the same sequence-specific cleavage reaction as does the hammerhead ribozyme and contain the conserved nucleotide sequences of the hammerhead ribozymes.

[A case report of mitral valve replacement for infective endocarditis in pregnancy]

Infective endocarditis in pregnancy is uncommon. A 37-week pregnant woman presented with infective endocarditis. Echocardiography revealed prominent mitral valve vegetations. The patient underwent cesarean section and a 2,800 g male infant was delivered. In order to prevent embolization, mitral valve replacement was performed 3 days after cesarean section with SJM valve. Both mother and child are doing well now.

Use of enzymatic activity for design of orally administered enteric dosing forms

Liquid and semi-solid enteric dosage forms were prepared by entrapping drug with an appropriate partition coefficient in a lipid base vehicle which would then be released by the action of intestinal enzymes. Lipid ester derivatives such as glyceryl monocaprylate and polysorbate 80 were used as vehicles. These vehicles readily dissolved the poorly water-soluble compounds used in the study, itazigrel, indomethacin and the dye, sudan II, and were digested by lipase and esterase, releasing the test drugs with time profiles similar to those observed in dissolution studies. The vehicles released little or only a small amount of the drugs into aqueous medium in the absence of an appropriate enzyme. The enzyme-sensitive enteric vehicles when containing sudan II did not release the dye in the stomach of rats after oral administration, but released significant amounts of the dye in the small intestine.

[Three cases of left atrial myxoma]

Three cases of left atrial myxoma are presented. All of them were diagnosed by echocardiography, computed tomography and cardiovascular angiography. At operation, origin of the tumors were found to arise from the vicinity of the fossa ovalis in two cases and the lower atrial septum in the other. Three different operative maneuvers were used in these three cases. In the first case, the left atrium was incised and the tumor was removed submucosally. In the second case, the left and right atrium were incised and the tumor was removed with atrial septum. In the third case, only the right atrium was incised and the tumor was removed with atrial septum. In comparison of these three different maneuvers, we conclude that the second case was most appreciable, because the operator could see whole sight of the left atrial cavity and whole contour of the tumor and remove the tumor completely without destruction. All these patients have done well for periods of follow-up ranging from 10 to 37 months.

[A case of ventricular septal defect with tricuspid regurgitation complicating infective endocarditis]

A unique case of 52-year-old woman with a ventricular septal defect associated with tricuspid regurgitation complicating infective endocarditis was reported. Under cardiopulmonary bypass, the VSD was closed directly and tricuspid valve was replaced with a Carpentier-Edwards valve. Intraoperative examination showed that the VSD was perimembranous type (5 mm in diameter), all three leaflets were destroyed and one chordae of anterior leaflet was ruptured. Her postoperative course was uneventful and she has been well.

[Total anomalous pulmonary venous connection in adult: report of a case]

Total anomalous pulmonary venous connection (TAPVC) is a cardiac disorder that seldom permits survival into adulthood without surgical correction in infancy. We reported a successful total correction in a 47-year-old man with TAPVC. Cardiovascular angiography demonstrated the features of Darling I a type TAPVC. Cardiac catheterization showed Qp/Qs: 5.8, Pp/Ps: 0.31, Rp/Rs: 0.06 and mild pulmonary hypertension. On operation, the posterior wall of left atrium anastomosed to the common pulmonary vein over 4 cm length, ASD (5.0x3.8 cm) was closed with patch, and the communicating vein was ligated. The patient made uneventful postoperative recovery and is well 3 months following surgery.

Intrapericardial aneurysm of the left atrial appendage

A 24-year-old housewife with congenital aneurysm of the left atrial appendage underwent a successful operation for its removal. Operation, using cardiopulmonary bypass, is indicated in all patients with atrial aneurysm. The procedure has proved uniformly safe and successful.